520 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



Gen. Tarentula Sand., 1833. 

 28. T. modesta n. 



Cephalothorax longer than patella + tibia of the fourth pair, blac kish 

 brown, with a broad pale brownish-gray, longitudinal middle band, 

 legs brown, the thighs shghtly black-spotted on the sides ; fourth pair 

 thrice as long as cephalothorax ; abdomen blackish, covered with 

 blackish- or grayish-brown hair above, the belly black ; vulva consisting 

 of a semi-elliptical brown fovea, the lateral margins of which are behind 

 dilated into two large transverse tubercles ; it is provided with a fusi- 

 form septum dilated at its posterior extremity into two costre, the whole 

 septum thus forming a JL, the transversal bars of which are long and 

 slightly sinuated. — 9 ad. Length about 12 millim. 



Female. — Cephalothorax somewhat longer than tibia + patella of the 

 fourth pair, its breadth equaling tibia -f half the patella (= metatar- 

 sus) of the fourth pair ; moderately rounded at the sides, broad in front, 

 the breadth of the clypeus nearly equaling three-fifths of the greatest 

 breadth of the pars thoracica; seen in profile, the back is slightly con- 

 vex between the posterior declivity and the hindmost eyes; the sides of 

 the pars cephalica are, seen from in front, strongly sloping, rounded ; 

 the height of the face is not much more than half the length of the 

 mandibles. First series of eyes little shorter than second row, slightly 

 curved downward, with the central eyes somewhat larger than the 

 laterals, and separated by an interval somewhat larger than that 

 between them and the lateral eyes, and smaller than their diameter. 

 Area occupied by the posterior eyes somewhat longer than broad in front, 

 much broader behind than in front ; ^j)ace between the two largest eyes 

 evidently smaller than their diameter, the spaee between them and the 

 hindmost eyes about half again as great as the diameter of these latter 

 eyes. Mandihles as thick as in the fore thighs, somewhat more than 

 double as long as broad at the base, as long as the metatarsi of the 

 second pair ; the claw-furrow has three strong teeth on the posterior and 

 two teeth on the anterior margin. Falpi slender, their tibial joint more 

 than double as long as broad. Legs strong, fourth pair thrice as long 

 as cephalothorax ; their spines are short; tibia of the first pair is armed 

 with 2. 2. 2. spines beneath and 1. in front (toward the apex) ; tibia of the 

 second pair with 2. 2. 2. spines beneath and 1. 1. in front. Abdomen of 

 the ordinary form ; the vulva is a corneous semi-elliptical fovea of 

 moderate size (its lengtli equals the diameter of the hindmost tibia), 

 rounded in front, truncate behind, somewhat longer than broad, and 

 limited by a sharp edge, which, at the posterior ends of the vulva, on 

 each side, is dilated into a large transverse shining tubercle ; all along 

 the bottom of the vulva is a rather narrow somewhat fusiform septum, 

 which at its posterior end is suddenly dilated and produced trausversally 

 into a costa (behind the above mentioned tubercles), thus forming a' 

 _L, the transverse bars of which are slightly sinuated, or ~ -shaped, and 

 together nearly as long as the longitudinal bar. 



